The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
Ensuring that media presentations are synchronized can be a tricky business. Delays could occur between one stream and another stream, or between one display and another display, which need to be accounted for so that all streams and/or all displays are synchronized with one another. CA 2,231,780 to Kerr and CA 2,491,522 to Jayant both teach systems that introduce a clock sample into a digitized audio stream and a digitized video stream. The clock samples could be compared against one another to ensure that the streams are synchronized with one another, and when the streams lose synchronization, a delay could be applied to the quicker stream to ensure that the streams are synchronized. Kerr and Jayant's system, however, only allows a single video stream to sync with a single audio stream on a single display device. Sometimes, a stream needs to be synced with a plurality of displays.
US 2009/0205008 to Wollmershauser teaches a system that allows a system to sync a plurality of remote devices, such as set top boxes, with one another by using frame identification values, such as hash values or sequential identifiers. A master set top box pings other set top boxes with the identifier of a frame that is being displayed. This ping is used by other set top boxes to synchronize those set top boxes with the master, and ensure that all of the set top boxes are simultaneously broadcasting a stream in sync. Wollmershauser, however, requires each frame to already have an identifier to broadcast that all set top boxes recognize. Many encoded streams are not encoded with frame identifiers that can universally be analyzed or broadcast.
US 2011/0010739 to Yun teaches a method for transmitting a stereoscopic video to a left view and a right view. Yun's video generation unit takes an inputted video signal and uses it to encode a stream with a Decoding Time Stamp (DTS) or a Presentation Time Stamp (PTS). Either time stamp could be inserted into the stream based on a system clock, and the system then synchronizes the left and right views based on the inserted time stamp. Yun's video generation unit, however, takes time to encode the inputted video signal into an encoded signal, which is fine for low-resolution or computer-generated input streams, but can be too slow for real-time high-definition streams, such as live video streams of HD sports or news broadcasts.
Thus, there remains a need for a system and method that synchronizes media stream presentations.